"HUMMINGBIRD MORNINGS"The final Hummingbird Mornings presentations scheduled for 2002 will be at Brookgreen Gardens south of Myrtle Beach SC on
24-25 August.
Click on the image at left for details.

If your group would like to host "Hummingbird Mornings" anywhere in the U.S. or Canada in 2002 or later, contact Bill Hilton Jr.

BIG GREEN MONSTER?

If you have recurring nightmares of being consumed by a big green monster, you might not want to stare too long at the photo below, else this surrealistic image taken at Hilton Pond Center is certain to awaken you suddenly in the middle of the night for the next several weeks. But if you're curious as to what this translucent blob might be, read on.

Although the photo does indeed look a little like something out of a spooky Steven Spielberg movie, it's actually a lateral closeup of the caterpillar of a Luna Moth, Actias luna. Found across eastern North America, the Luna Moth (left) is in the Saturniidae, the family that includes Giant Silkworm Moths; these are large moths with wingspans of up to almost 6", but the 5" Luna Moth appears even larger because of long tails on its hindwings. Despite their name, Giant Silkworm Moths (including Cecropia, Polyphemus, and Promethea Moths) are unrelated to commercially important Asiatic silkworms, which are in the Bombycid Family.

Saturnids typically have wings marked by "eyespots"--perhaps an adaptation that scares off potential predators. The eyespots are especially noticeable against the uniform pale green of a Luna Moth's wings (above). Another obvious characteristic of a typical adult Giant Silkworm Moth is its large, feathery "plumose" antennae (below left). In the male Luna Moth, these receptors are especially large and adept at picking up minute traces of pheromones--chemicals released by the female that allow males to track her down in complete darkness, or as she flutters against a backlit window at night. After the female lays several clusters of tiny black eggs, her caterpillars hatch, go through a series of growth stages, and eventually form a papery, thin-walled cocoon on the ground. In warmer parts of the Luna Moth's range, there are two complete generations per year.

Luna Moth caterpillars, which reach lengths of slightly more than 3", are voracious eaters that dine on leaves of hickories, walnuts, birches, Common Persimmon, and Sweet Gum. Like other caterpillars, their multiple mouthparts are adapted for chewing, and they easily make short work of a tasty leaf. Just behind the caterpillar's head (right)--which is quite small by comparison to its body--are the three pairs of "true legs" that reveal its true classification as a six-legged insect. Since those legs are so close to its anterior end, the caterpillar would likely have trouble controlling a lengthy posterior. The hind end is supported by prolegs--"false legs" that can cling to to twigs and branches and move the body along (top and below left). One pair of prolegs grows from each of five abdominal segments, and the terminal ones are modified further into an opposable grasping pair. Despite being well-formed and highly functional in the Luna Moth's larval stage, all the false feet disappear when a caterpillar metamorphoses into an adult.

Luna Moths have been hurt by habitat loss in many parts of their range--they were far more common before American Chestnuts were eliminated as a food source for their larvae--and some populations have been decimated by indiscriminate spraying of pesticides. At Hilton Pond Center, we avoid the latter and encourage the growth of hickory, walnut, and persimmon trees, so we like to think we're doing our part to make sure the fascinating Luna Moth caterpillar and its showy adult form can be found here for generations to come.

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Hilton Pond Center for Piedmont Natural History is a non-profit research & education organization in York, South Carolina USA; phone (803) 684-5852. Directed by Bill Hilton Jr., aka The Piedmont Naturalist, it is the parent organization for Operation RubyThroat. Contents of this Web site--including articles and photos--may NOT be duplicated, modified, or used in any way except with the express written permission of Hilton Pond Center. All rights reserved worldwide. To obtain permission for use or for further assistance on accessing this Web site, contact the Webmaster.